NGTS-1

NGTS-1
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Columba
Right ascension 05h 30m 51.45227s[1]
Declination −36° 37′ 50.8957″[1]
Apparent magnitude (V) 15.57±0.03[2]
Characteristics
Evolutionary stage main sequence star[3]
Spectral type M0.5[3]
B−V color index +1.37[2]
R−I color index +1.39[4]
Astrometry
Radial velocity (Rv)97.18±0.01[3] km/s
Proper motion (μ) RA: −31.887 mas/yr[1]
Dec.: −41.077 mas/yr[1]
Parallax (π)4.5935 ± 0.017 mas[1]
Distance710 ± 3 ly
(217.7 ± 0.8 pc)
Details[3]
Mass0.617+0.023
−0.062 M☉
Radius0.573±0.077 R☉
Luminosity(7.03±0.09)×10−2[5] L☉
Surface gravity (log g)4.71±0.23 cgs
Temperature3,916+71
−63 K
Rotational velocity (v sin i)<1.0 km/s
Other designations
UCAC2 16099071, NGTS-1, UCAC4 267-006604, DENIS J053051.4-363750, TIC 192826603 USNO-B1.0 0533-00066386, 2MASS J05305145-3637508,UCAC3 107-15281, Gaia DR2 4821739369794767744
Database references
SIMBADdata
Exoplanet Archivedata

NGTS-1, also designated as TOI-551 is a solitary star located in the southern constellation Columba, the dove. With an apparent magnitude of 15.52,[2] NGTS-1 can only be seen through a powerful telescope. Gaia DR3 parallax measurements imply a distance of 710 light-years[1] and it is drifting away rapidly with a heliocentric radial velocity of 97.2 km/s.[3]

Properties

NGTS-1 has a stellar classification of M0.5, indicating that is an early M-type star. It has 61% of the mass of the Sun and over half of its radius.[3] Since red dwarfs are fully convective, they do not burn as much as more massive stars. As a result, NGTS-1 only radiates 7.02% of the luminosity of the Sun from its photosphere at an effective temperature of 3,916 K.[3] There was difficulty determining the metallicity of the object due to its faintness, but NGTS-1 is assumed to be around solar metallicity.[3] In addition, this also provided some uncertainty about the star's properties since red dwarfs properties are dependent on their metallicity. It spins too slowly for it to be measured accurately, having a projected rotational velocity lower than 1.0 km/s.[3]

Planetary system

The discovery of a hot Jupiter orbiting the star was reported in 2017 as part of the Next Generation Transit Survey.[3] The media also dubbed NGTS-1b as "monstrous" since the planet is relatively large compared to its host star.[6]

The NGTS-1 planetary system[3]
Companion
(in order from star) 		Mass Semimajor axis
(AU) 		Orbital period
(days) 		Eccentricity Inclination Radius
b 0.812+0.066
−0.075 MJ 		0.0326+0.0047
−0.0045 		2.6473068±0.0000017[7] 0.016+0.023
−0.012 		85.27+0.61
−0.73° 		1.33+0.61
−0.33 RJ

References

  1. ^ a b c d e Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  2. ^ a b c Zacharias, N.; Finch, C. T.; Girard, T. M.; Henden, A.; Bartlett, J. L.; Monet, D. G.; Zacharias, M. I. (2013-02-01). "The Fourth US Naval Observatory CCD Astrograph Catalog (UCAC4)". The Astronomical Journal. 145 (2): 44. arXiv:1212.6182. Bibcode:2013AJ....145...44Z. doi:10.1088/0004-6256/145/2/44. ISSN 0004-6256. S2CID 119299381.
  3. ^ a b c d e f g h i j k Bayliss, Daniel; Gillen, Edward; Eigmuller, Philipp; McCormac, James; Alexander, Richard D.; Armstrong, David J.; Booth, Rachel S.; Bouchy, Francois; Burleigh, Matthew R.; Cabrera, Juan; Casewell, Sarah L. (April 21, 2018). "NGTS-1b: A hot Jupiter transiting an M-dwarf". Monthly Notices of the Royal Astronomical Society. 475 (4): 4467–4475. arXiv:1710.11099. Bibcode:2018MNRAS.475.4467B. doi:10.1093/mnras/stx2778. ISSN 0035-8711.
  4. ^ Denis, Consortium (2005-09-01). "VizieR Online Data Catalog: The DENIS database (DENIS Consortium, 2005)". VizieR Online Data Catalog: B/denis. Bibcode:2005yCat.2263....0D.
  5. ^ Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  6. ^ "NGTS-1b – Scientists Find a Baffling New Monster Planet". Facts Legend. 2017-11-06. Archived from the original on 2018-01-14. Retrieved 2021-02-18.
  7. ^ Kokori, A.; et al. (March 1, 2023). "ExoClock Project. III. 450 New Exoplanet Ephemerides from Ground and Space Observations". The Astrophysical Journal Supplement Series. 265 (1): 4. arXiv:2209.09673. Bibcode:2023ApJS..265....4K. doi:10.3847/1538-4365/ac9da4. ISSN 0067-0049. S2CID 252383631.